1. Field of the Invention
The present invention relates to a control for a paperwinder, and is more particularly concerned with controlling the winder to stop at a preset web length or a preset roll diameter.
2. Description of the Prior Art
Papermill customers generally purchase finished paper rolls specified to a guaranteed sheet length on the roll or a roll wound to a guaranteed diameter. Controls are commercially available for stopping a winder at a preset sheet length, but not to a specified roll diameter. Also, conventional stop-to-length controls do not provide closed loop control of winder deceleration and, instead, utilize a two-level stop mode. The winder deceleration starts at an initial set point at a rate fixed by the drive, and continues to some preset slow speed. The winder then runs at this low speed to the second or final stop point. This method can achieve accurate sheet length control; however, it requires a longer stopping time.
The ASEA Rolltrimmer is a system of the type set forth above with respect to stop-to-length control.
Schommeier U.S. Pat. No. 4,438,889 discloses a computer system for controlling stopping length by switching the drive control between two rates of deceleration; one slightly greater than the desired rate and one slightly less than the desired rate.